► Oxidative stress plays a role in neurodegenerative processes. ► Thirteen herbal extracts tested for protection against H₂O₂ induced cell death. ► Polygonum multiflorum was the most potent antioxidant and cytoprotectant. ► Total phenol content was strongly correlated with antioxidant capacity. ► Antioxidant activity is moderately correlated with cytoprotective ability.

 Introduction

For millennia, herbal medicines consisting of whole herbs or plant parts such as leaves, stems, roots and seeds have been used in traditional Chinese medicine (TCM) for the treatment of specific ailments, to maintain and restore body balance and to increase longevity (Suk, 2005). Many of the drugs available in Western medicine have been directly isolated from plants or are hemi-synthetic molecules based on the molecular scaffolds of natural products. While Western medicine mainly focuses on the identification and isolation of single active constituents from plants that interact with single therapeutic targets, TCM aims to reverse the underlying “imbalance” between the body and the environment that is thought to cause disease (Cheng, 2000). This often involves the use of complex mixtures of herbs containing multiple chemical groups and compounds with diverse biological and pharmacological actions. It is believed that compounds not only act synergistically with other compounds from the same plant, but also may enhance the activity or counteract the toxicity of compounds from other plants (Howes and Houghton, 2003). A recent study, investigating the antioxidant properties of a herb which is used extensively in TCM, Polygonum multiflorum, found that the radical scavenging abilities of two of its main active components, emodin and quercetin, were lower than crude leaf, stem and root extracts of the herb (Lin et al., 2010). Furthermore, while studies with traditional herbal medicines such as Fuzhisan (Bi et al., 2011) and herbal extracts such as Panax ginseng(Lee et al., 2008) have shown success in slowing cognitive decline; results of clinical trials with single “active” compounds, such as curcumin from Curcuma longa (Hamaguchi et al., 2011) and huperzine A fromHuperzia serrata (Rafii et al., 2011) have not been successful.

Full Article can be found here http://www.sciencedirect.com/science/article/pii/S0197018612002860

Cytoprotective properties of traditional Chinese medicinal herbal extracts in hydrogen peroxide challenged human U373 astroglia cells

• Megan L. Steele^a,
• John Truong^c, 1,
• Suresh Govindaraghavan^a, d, 2,
• Lezanne Ooi^a,
• Nikolaus J. Sucher^c, 1,
• Gerald Münch^a, b, , 

• ^a Dept. of Pharmacology, School of Medicine, University of Western Sydney, Campbelltown, NSW, Australia
• ^b Molecular Medicine Research Group, University of Western Sydney, Campbelltown, NSW, Australia
• ^c CompleMed, University of Western Sydney, Campbelltown, NSW, Australia
• ^d LIPA Pharmaceuticals, Minto, NSW, Australia